Nitrogen-, phosphorus- and sulfur-containing lubricant additives

ABSTRACT

Compositions useful as antioxidants, corrosion inhibitors and extreme pressure agents in lubricants are prepared from hydrazine or a substituted hydrazine, carbon disulfide, and the product obtained by reacting a hydroxy-substituted phosphorothioic acid triester with an inorganic phosphorus acid, oxide or halide and neutralizing a substantial portion of the acidic intermediate thus obtained with an amine.

United States Patent Allen [151 3,655,556 [451 Apr. 11, 1972 [54]NITROGEN-, PHOSPHORUS- AND SULFUR-CONTAINING LUBRICANT ADDITIVES [72]inventor: John Wight Allen, Euclid, Ohio [7 3] Assignee: The LubrizolCorporation, Wickliffe, Ohio [22] Filed: Aug. 14, 1970 2] Appl. No.263,946

[52] US. Cl ..252/32.7 E, 252/46.7, 252/389,

[51] int. Cl. ..Cl0m l/48 [58] Field of Search ..252/46.7, 32.7 E, 389,400; 260/132, 127

[56] References Cited UNITED STATES PATENTS 2,966,462 12/1960 Spindt etal. ..252/32.7 E

3,182,021 5/1965 Asseff ..252/46.6 3,197,405 7/1965 Le Suer.....252/32.7 E 3,197,496 7/1965 Le Suer ..252/32.7 X

Primary Examiner-Daniel E. Wyman Assistant Examiner-W. H. CannonAttorney-Roger Y. K. l-lsu, William H. Pittman and James W. Adams, Jr.

[5 7] ABSTRACT 19 Claims, No Drawings NlTROGEN-, PHOSPHORUS ANDSULFUR-CONTAINING LUBRICANT ADDITIV ES This invention relates to newcompositions of matter useful as lubricant additives, particularly ascorrosion and rust inhibitors and for the improvement of extremepressure properties. More particularly, it relates to novel compositionsof matter prepared by bringing into contact, under conditions such thata chemical reaction can take place, (A) a compound of the formulawherein each of R, R and R is hydrogen or a hydrocarbon or substitutedhydrocarbon radical; (B) carbon disulfide; and (C) a compositionprepared by forming an acidic intermediate by the .reaction of ahydroxy-substituted triester of a phosphorothioic acid with an inorganicphosphorus acid, oxide or halide and neutralizing a substantial portionof said acidic intermediate with an amine.

Modern lubricants, including engine oils, gear lubricants, automatictransmission fluids and the like, owe their efficiency in large part tothe presence therein of numerous additives which improve variousproperties of the lubricant. Many of these additives, however, cause newproblems of their own when they are added to the lubricant. For example,sulfurcontaining compounds are often used to improve extreme pressureproperties of lubricants, especially gear oils and the like, but thesesulfur compounds have a strong tendency to cause corrosion of metalparts, especially bearings which may contain copper, silver or othersulfur-reactive metals. Therefore, it is of continuing interest todevelop lubricant additives which improve extreme pressure propertiesand at the same time inhibit corrosion and rust of the metal surfaceswith which they come in contact.

A principal object of the present invention, therefore, is to preparenew compositions of matter suitable for use as lubricant additives.

A further object is to prepare lubricant additives which protect metalsurfaces from rust and corrosion and which improve the extreme pressureproperties of the lubricant.

Other object will in part be obvious and will in part appearhereinafter.

Component A in the compositions of this invention is hydrazine or asubstituted hydrazine. The corresponding hydrazine hydrate may also beused. For reasons of economy and particular suitability, unsubstitutedhydrazine (N H is preferred; but hydrazines substituted (eithersymmetrically or unsymmetrically) with from one to three hydrocarbon orsubstituted hydrocarbon radicals are also suitable. The term hydrocarbonradical" as used herein includes aliphatic, cycloaliphatic and aromatic(including aliphaticand cycloaliphatic-substituted aromatic andaromatic-substituted aliphatic and cycloaliphatic) radicals. it alsoincludes cyclic radicals wherein the ring is completed through anotherportion of the molecule; that is, any two indicated substituents maytogether form a cycloalkyl radical.

The following are illustrative of hydrocarbon radicals within the scopeof this invention. Where a named radical has several isomeric forms(e.g., butyl all such forms are included.

Methyl Benzyl Ethyl Cyclohexyl Propyl Cyclopentyl ButylMethylcyclopentyl Hexyl Cyclopentadienyl Octyl Vinylphenyl Decyllsopropenylphenyl Vinyl Cinnamyl Allyl Naphthyl Ethynyl Propargyl PhenylTolyl -CH2CII- Many obvious variations of these radicals will beapparent to those skilled in the art and are included within the scopeof the invention.

The term hydrocarbon radical includes substituted hydrocarbon radicals.By substituted is meant radicals containing substituents which do notalter significantly the character or reactivity of the radical. Examplesare:

Halide (fluoride, chloride, bromide, iodide) Hydroxy Ether (especiallylower alkoxy) Keto Aldehyde Ester (especially lower carbalkoxy)Aminoacyl (amide) Nitro Cyano Thiocther Sulfoxy Sulfonc In general, nomore than about three such substituent groups will be present for each10 carbon atoms in the radical.

' Preferably, the hydrocarbon or substituted hydrocarbon radicals in thecompounds of this invention are free from ethylenic and acetylenicunsaturation and have no more than about 30 carbon atoms, desirably nomore than about 12 carbon atoms. A particular preference is expressedfor lower hydrocarbon radicals, the word lower denoting radicalscontaining up to seven carbon atoms. Still more preferably, they arelower alkyl or aryl radicals, most often alkyl.

Examples of substituted hydrazines useful as component A aremethylhydrazine, N,N-dimethylhydrazine, N,N-dimethylhydrazine,N,N,Nphenylhydrazine, N-phenyl-N-ethylhydrazineN-phenyl-N,N'-diethylhydrazine; N-(p-tolyl)-N'- (n-butyl)-hydrazine,N-(p-nitrophenyl)-N-methylhydrazine, N,N'-di(p-chlorophenyl)hydrazineand N-phenyl-N- cyclohexylhydrazine.

Component B is carbon disulfide. It may be used in the free state or inthe form of carbon disulfide-producing compounds such as metaltrithiocarbonates, dithiocarbamates or xanthates.

Component C is a composition prepared by neutralizing with an amine theacid formed by reacting a hydroxy-substituted phosphorothioic acidtriester with an inorganic phosphorus acid, oxide or halide. Suchcompositions are disclosed in detail in U.S. Pat. No. 3,197,405, thedisclosure of which is incorporated by reference herein.

The hydroxy-substituted triesters of phosphorothioic acids useful forthe preparation of component C include principally those having thestructural formula wherein each R is a hydrocarbon or substitutedhydrocarbon radical (as defined hereinabove) or a hydroxy-substitutedderivative thereof, at least one of the R radicals beinghydroxy-substituted, and each X is sulfur or oxygen, at least one of theX radicals being sulfur. A preferred class of hydroxy-substitutedtriesters comprises those having the structural formula wherein R is amonovalent and R is a divalent hydrocarbon or substituted hydrocarbonradical. A convenient method for preparing such esters involves thereaction of a phosphorodithioic acid with an epoxide or a glycol. Thisreaction is known in the art; the following equations are illustrative.

Exemplary epoxides are ethylene oxide, propylene oxide, styrene oxide,a-methylstyrene oxide, p-methylstyrene oxide, cyclohexene oxide,cyclopentene oxide, 2,3-butene oxide, 1,2-butene oxide, 1,2-octeneoxide, 3,4-pentene oxide, and 4- phenyl-l ,2-cyclohexene oxide. Forreasons of economy, lower aliphatic epoxides and styrene oxides arepreferred for use in this process.

Glycols which may be used include both aliphatic and aromatic dihydroxycompounds. Aliphatic glycols such as ethylene glycol, trimethyleneglycol, tetramethylene glycol, hexamethylene glycol, propylene glycol,pentylene glycol, decamethylene glycol, diethylene glycol, triethyleneglycol, and pentaethylene glycol are especially useful. Also suitableare aromatic dihydroxy compounds such as hydroquinone, catechol,resorcinol and l,2-dihydroxynaphthalenes.

Another convenient method for preparing the hydroxy-substitutedtriesters is described in U.S. Pat. No. 2,528,732 and comprises theaddition of a phosphorodithioic acid to an unsaturated alcohol such asallyl alcohol, cinnamyl alcohol, or oleyl alcohol. Still another methoddescribed in US Reissue Pat. No. 20,411, involves the reaction of ametal phosphorothioate with a halogen-substituted alcohol.

The phosphorodithioic acids from which the hydroxy-substituted triesterscan be derived are likewise well known. They are prepared by thereaction of phosphorus pentasulfide with an alcohol or a phenol. Thereaction involves 4 moles of the alcohol or phenol per mole ofphosphorus pentasulfide and may be carried out at about 50200 C. Thus,the preparation of 0,0-di-n-hexylphosphorodithioic acid involves thereaction of phosphorus pentasulfide with 4 moles of n-hexyl alcohol atabout 100 C. for about 2 hours. Hydrogen sulfide is liberated and theresidue is the desired acid.

The preparation of phosphoromonothioic acids may be effected bytreatment of the corresponding phosphorodithioic acids with steam.Phosphorotrithioic acids and phosphorotetrathioic acids can be obtainedby the reaction of phosphorus pentasulfide with mercaptans or mixturesof mercaptans and alcohols.

The reaction of phosphorus pentasulfide with a mixture of phenols oralcohols (e.g., isobutanol and n-hexanol in 2:1 weight ratio) results inphosphorodithioic acids in which the two organic radicals are different.Such acids likewise are useful for the preparation of component C.

The inorganic phosphorus reagent useful in the reaction with thehydroxy-substituted triesters of phosphorothioic acids is preferablyphosphorus pentoxide. Other phosphorus oxides such as phosphorustrioxide and phosphorus tetroxide likewise are useful, as are phosphorusacids (e.g., phosphoric monobromophosphorus tetrachloride, ychloride andphosphorus triiodide).

Usually, from about 2 moles to about 5 moles of the triester for eachmole of the inorganic phosphorus reagent. The preferred proportion ofthe triester is about 3-4 moles for each mole of the phosphorus reagent.The use of amounts of either reactant outside the limits indicated hereresults in excessive unused amounts of the reactant and is ordinarilynot preferred.

The reaction of the hydroxy-substituted triester with the inorganicphosphorus reagent to produce the acidic intermediate can be effectedsimply by mixing the two reactants at a temperature above about roomtemperature, preferably above about 50 C. A higher temperature such asC. or C. may be used but ordinarily is unnecessary.

The reaction of the hydroxy-substituted phosphorothioic acid triesterwith the inorganic phosphorus reagent results in an acidic product. Thechemical constitution of the acidic product depends to a large measureon the nature of the inorganic phosphorus reagent used. In mostinstances the product is a complex mixture the precise composition ofwhich is not known. It is known, however, that the reaction involves thehydroxy radical of the triester and the inorganic phosphorus reagent. Inthis respect the reaction may be likened to that of an alcohol or aphenol with the inorganic phosphorus reagent. Thus, the reaction of thehydroxy-substituted triester with phosphorus pentoxide is believed toresult principally in acidic phosphates, i.e., monoor diesters ofphosphoric acid in which the ester radical is the residue obtained bythe removal of the hydroxy radical of the phosphorothioic triester. Theproduct may also contain phosphonic acids and phosphinic acids in whichone or two direct carbon-to-phosphorous linkages are present.

The reaction between the hydroxy-substituted triester and a phosphorusoxyhalide or phosphoric acid is believed to result in similar mixturesof acidic phosphates, phosphonic acids and/or phosphinic acids. On theother hand, the reaction of the hydroxy-substituted triester withphosphorus tri-chloride or phosphorous acid is believed to resultprincipally in acidic organic phosphites. Still others products may beobtained from the use of other inorganic phosphorus reagents. In anyevent, the product is acidic and as such is useful as the intermediatefor the preparation of component C.

In the second step of the reaction sequence leading to component C. theabove-described acidic intermediate is neutralized with an amine. Theamine may be aliphatic, aromatic, cycle-aliphatic or heterocyclic.Examples are:

phosphorus oxn-Butylamine Stearylamine n-Hexylamine Eisosylaminen-Octylamine Behenylamine t-Octylamine Tetracosylaminen-Methyloctylumine Hexatriacontylamine CyclopentylaminePentahexacontylamine Cyclohexylamine Menthanediamine n-DecylamineEthylenediamine n-Dodecylamine Di-n-dodecylamine Tri-n-dodecylamineHexamethylenetetraminc Octamethylenediamine n-DodecyltrimethylenediamincAlso useful are hydroxy-substituted amines such as the following:

Ethanolamine Diethanolamine Triethanolamine lsopropanolaminep-Aminophenol 4-Aminol -naphthol The preferred amines are aliphaticamines having about four to 30 carbon atoms, especially those containingat least about eight carbon atoms. A particular preference is expressedfor primary amines containing tertiary alkyl groups, especially acommercially available mixture of C tertiary alkyl primary amines.

Among the hydroxy-substituted amines, a particular preference isexpressed for secondary or tertiary aliphatic amines in which one of thesubstituents on nitrogen is a hydroxyalkylene or poly-(oxyalkylene)radical. Examples of the latter are N-4-hydroxybutyldodecylamine,N-Z-hydroxyethyl-n-octylamine, N-2-hydroxypropyldinonylamine, N,N-di-(3-hydroxypropyl)-t-dodecylamine,N-hydroxytriethoxyethyl-t-tetradecylamine,N-2-hydroxy-ethyl-t-dodecylamine,N-hydroxyhexapropoxypropyl-t-octadecylamine and N-5-hydroxypentyl-di-n-decy1amine. Amines of this type may be prepared byreacting an aliphatic primary or secondary amine with at least anequimolar amount of an epoxide, preferably in the presence of a highlybasic catalyst such as sodium methoxide, sodamide, sodium metal or thelike. Especially preferred are amines of this type wherein the alkylsubstituents are tertiary alkyl radicals containing about 11-24 carbonatoms, It is frequently convenient and desirable to use a mixture ofcompounds of this type which may be prepared by the reaction of anepoxide with the commercial C,, tertiary alkyl primary amine mixturedescribed above.

The relative proportions of the acidic intermediate and the amine usedin the reaction should be such that a substantial portion of the acidicintermediate is neutralized. In most instances, enough amine should beused to neutralize at least about 50 percent of the acidic intermediate.Substantially neutral products such as are obtained by neutralization ofat least about 90 percent of the acidity of the intermediatearedesirable.

The neutralization of the acidic intermediate with the amine is in mostinstances exothermic and can be carried out simply by mixing thereactants at ordinary temperatures, preferably about 0-200 C. Thechemical constitution of the neutralized product of the reaction dependsto a large extent upon the temperature. Thus, at a relatively lowtemperature, such as less than about 80 C., the product comprisespredominantly a salt of the amine with the acid. At a temperature aboveabout 100 C., the product may contain amides, amidines, or mixturesthereof. The reaction of the acidic intermediate with a tertiary amineresults only in a salt.

The preparation of compositions useful as component C is illustrated bythe examples in the above-mentioned US. Pat. No. 3,197,405, andespecially by the following.

EXAMPLE 1 Phosphorus pentoxide (64 grams, 0.45 mole) is added at 58 C.over 45 minutes to hydroxypropyl 0,0-di(4-methyl-2-pentyl)-phosphorodithioate (514 grams, 1,35 moles), which is prepared bytreating di(4-methy1-2-pentyl)phosphorodithioic acid with 1.3 moles ofpropylene oxide at 25 C. The mixture is heated at 75 C. for 2% hours,mixed with a filter aid, and filtered at 70 C. To 217 grams (0.5equivalent) of the filtrate there is added over minutes, at -60 C., 66grams (0.35 equivalent) of a commercial aliphatic primary amine havingan average molecular weight of 191 in which the aliphatic radical is amixture of tertiary alkyl radicals containing 11-14 carbon atoms. Thepartially neutralized product contains 10.2% phosphorus and 1.5%nitrogen.

EXAMPLE 2 A mixture of 442 grams (0.925 mole) of hydroxypropyl0.0-bis(dichlorophenyl)phosphorodithioate, prepared by the reaction ofbis(dichlorophenyl) phosphorodithioic acid with 1.1 moles of propyleneoxide at -90 C., and 43.6 grams (0.308 mole) of phosphorus pentoxide isheated at 140 C. for 0.5 hour, at 120l25 C. for 3 hours, and at 155-160C. for

1 hour. The acidic intermediate thus obtained is neutralized bytreatment at 1 10-120 C., for 2% hours, with 238 grams of a commercialaliphatic primary amine having an average molecular weight of 315 inwhich the aliphatic radical is a mixture of tertiary alkyl radicalscontaining from 18 to 22 carbon atoms. The neutralized product isfiltered; the filtrate contains 5.4% phosphorus, 8.2% sulfur, 17.8%chlorine, and 1.5% nitrogen.

EXAMPLE 3 A mixture of 710 grams (5 moles) of phosphorus pentoxide andhydroxypropyl 0,0-di(4-methyl-2-pen- EXAMPLE 4 Phosphorus pentoxide 142grams) is added at 75 C., over 1.2 hours, to 1,500 grams ofhydroxypropyl 0,0'-di(4-methyl- 2-pentyl)phosphorodithioate. The mixtureis heated at 75 C. for 3% hours and the liquid acidic product isseparated. To 1,591 grams of the liquid there is added at 70 C., over 15minutes, 700 grams of the aliphatic primary amine of Example 1. Theproduct is filtered. The filtrate contains 7.95% phosphorus, 10.75%sulfur, and 2.21% nitrogen.

EXAMPLE 5 Phosphorus pentoxide (53 grams, 0.35 mole) is added to 430grams (1.14 moles) of hydroxypropyl 0,0'-di(4-methyl-2-pentyl)-phosphorodithioate at -63 C. over 5.5 hours. The mixture isheated to 75-80 C. and held at that temperature for 2 hours. There isthen added 219 grams of the commercial aliphatic primary amine ofExample 1 at 3060 C. over 1.5 hours. The product is maintained at 50-60C. for 1% hour and filtered. The filtrate contains 8.0% phosphorus,10.4% sulfur, and 2.2% nitrogen.

EXAMPLE 6 Phosphorus pentoxide (33 grams) is added to 297 grams ofhydroxyoctyl dicyclohexylphosphorodithioate (prepared by reactingdicyclohexylphosphorodithioic acid with one mole of 1,2-octene oxide atroom temperature to 60 C.) at 75 C. over 45 minutes. The acidic reactionmixture is held at 75 C. for 4 hours and filtered. To 235 grams of theacidic filtrate there is added 115 grams of the commercial aliphaticprimary amine of Example 1 at room temperature to C. over 15 minutes.The product contains 6.87% phosphorus, 9.00% sulfur, and 2.32% nitrogen.

EXAMPLE 7 Phosphorus pentoxide (55.8 grams, 0.39 mole) is added at 6090C. to 1,358 grams (1.18 moles) of the hydroxypropyl ester of adi-(alkaryl)phosphorodithioic acid wherein the alkaryl groups arederived from a polyisobutenyl phenol in which the polyisobutenylradicals have a molecular weight of about 350. The mixture is heated at110 C. for 6 /2 hours and filtered. To 448 grams of the filtrate, thereis added at 65-84 C., 100 grams of a commercial N-aminopropyl tallowamine having a nitrogen content of 7 percent and the resulting mixtureis heated at C. for 40 minutes. The product contains 3.5% phosphorus,and 1.4% nitrogen.

EXAMPLE 8 Phosphorus thiochloride (PSCL 84.5 grams, 0.5 mole) is addedto 592 grams (1.5 moles) of hydroxypropyl 0,0'-di(4-methyl-Z-pentyl)phosphorodithioate at 30 C. The acidic reaction mixtureis heated to 85 C., held for 6 hours at this temperature, and mixed with281 grams (1.5 moles) of the aliphatic primary amine of Example 1 at 30C. to 60 C. The

product contains 6.85% phosphorus, 11.86% sulfur, and

2.18% nitrogen.

EXAMPLE 9 Phosphorus trichloride (46 grams, 0.33 mole) is added to 388grams (1 mole) of hydroxypropyl 0,0'-di(4-methyl-2-pentyl)phosphorodithioate at room temperature over 30 minutes. The mixture isheated to 80 C./ 15 mm. over 3 hours. To the acidic residue (393 grams)there is added 117 grams of the aliphatic primary amine of Example 1 atroom temperature to 1 5 45 C. The product contains 8.02% phosphorus,12.72% sulfur, and 1.64% nitrogen.

EXAMPLE Twelve moles (2,292 grams) of the primary amine of Exampie 1 isplaced in a reaction vessel and heated to 170 C. Sodium metal (0.6 gram)is added and then 528 grams (12 moles) of ethylene oxide is introducedinto the reaction vessel over hours at l65175 C. Thereafter, the wholeis stripped at 1 10 C./20 mm. Hg, diluted with '500 ml. of benzene,water- 25 washed, dried by azeotropic distillation, and filtered.

Five equivalents (2,330 grams) of phosphorus pentoxidetreatedhydroxypropyl 0,0-di-(4-methyl-2-pentyl)phosphorodithioate prepared in amanner similar to that set forth in Example 1 is introduced into areaction vessel and stirred. To it is added dropwise 1,180 grams (5equivalents) of the N-2-hydroxyethyl substituted amine mixture preparedas described above, over a period of 0.75 hour. An exothermic reactioncauses the temperature to rise to 60 C. After all of the amine has beenadded, the whole is stirred for 2 hours. The

resulting neutralized product contains 8.05% phosphorus, 2.03% nitrogen,and 10.16% sulfur.

The compositions of this invention are prepared by bringing theabove-described components into contact under conditions such that achemical reaction between them can take place (although, as explainedhereinafter, it is not certain what reaction, if any, does take place).This may be done, for example, by heating and agitating or by merelyagitating for a period of time sufficient for said reaction. Thepreparation is generally most conveniently carried out by maintaining amixture of the three components at a temperature of about 25-l00bL C.,preferably about -100 C. In general, no solvent is necessary, but asolvent inert to the reaction, such as a hydrocarbon, alcohol, ketone,ester or the like, may be used if so desired.

The proportions of the various reactants used are not critical.Generally, a mole ratio of component B to component A of about 2:1 isemployed, but this ratio may be higher,

frequently up to 5:1, or may be lower on occasion. The weight ratio ofcomponent C to component A is generally between about 75:1 and 500:1.

The chemical structure of the products formed by the method of thisinvention is not known. The products may contain such species asdithiocarbamates, nitrogen-sulfur hetero- 6O cyclic compounds,thiocyanates and the like, as well as unreacted components A, B and C,in various proportions. They can be adequately defined only in terms ofthe process for their preparation.

The preparation of the compositions of this invention is illustrated bythe following examples. All parts are by weight.

EXAMPLE 11 To a mixture of 1,320 parts of the product of Example 5 and3.1 parts of 95% aqueous hydrazine is added over 2 minutes,

with stirring, 14.2 parts of carbon disulfide. The mixture is heated to-90 C. for about 2% hours, and then volatile materials are stripped atC./50 mm. The residue is filtered, yielding the desired product whichcontains 11.24% sulfur,

8.21% phosphorus and 2.32% nitrogen. 75

EXAMPLE 12 Following the procedure of Example 1 l, a product containing11.38% sulfur, 8.33% phosphorus and 2.51% nitrogen is prepared from1,320 parts of the compositions of Example 5, 9.3 parts of hydrazinehydrate and 28.3 parts of carbon disulfide.

EXAMPLE 1 3 Following the procedure of Example 1 l, a product containing11.46% sulfur, 8.0% phosphorus and 2.75% nitrogen is prepared from 1,320parts of the composition of Example 5, 18.6 parts of hydrazine hydrateand 56.6 parts of carbon disulfide.

EXAMPLE l4 EXAMPLE 15 Following the procedure of Example 14, a productis prepared from 1,320 parts of the composition of Example 5, 18.6 partsof hydrazine hydrate and 113.2 parts of carbon disulfide.

EXAMPLE 16 Following the procedure of Example 14, a product is preparedfrom 1,320 parts of the composition of Example 5, 19 parts of thehydrazine hydrate and 65 parts of carbon disulfide.

EXAMPLE 17 Following the procedure of Example 14, a product is preparedfrom 1,320 parts of the composition of Example 5, 23 parts of hydrazinehydrate and 74 parts of carbon disulfide. It contains 1 1.6% sulfur and7.7% phosphorus.

EXAMPLE 18 Following the procedure of Example 14, a product is preparedfrom 1,807 parts of the composition of Example 5, 26 parts of hydrazinehydrate and 78 parts of carbon disulfide. It contains 8.15% phosphorus,11.44% sulfur and 2.54% nitrogen.

EXAMPLE 19 Following the procedure of Example 14, a product is preparedfrom 7,920 parts of the composition of Example 3, 340 parts of carbondisulfide and parts of N,N-dimethylhydrazine.

EXAMPLE 20 Following the procedure of Example 14, a product is preparedfrom 7,920 parts of the composition of Example 6, 340 parts of carbondisulfide and 135 parts of N,N-dimethylhydrazine.

EXAMPLE 21 Following the procedure of Example 14, a product is preparedfrom 7,920 parts of the composition of Example 9, 340 parts of carbondisulfide and 166.5 parts of trimethylhydrazine.

EXAMPLE 22 Following the procedure of Example 14, a product is preparedfrom 7,920 parts of the composition of Example 10, 340 parts of carbondisulfide and 135 parts of ethylhydrazine.

The compositions of this invention as previously indicated, are usefulin lubricants as oxidation and corrosion inhibitors and extreme pressureagents. As such, they can be employed in a variety of lubricatingcompositions based on diverse oils of lubricating viscosity, includingnatural and synthetic lubricating oils and mixtures thereof. Thelubricating compositions contemplated include principally gearlubricants. However, crankcase lubricating oils for spark-ignited andcompression-ignited internal combustion engines including automobile andtruck engines, two-cycle engine lubricants, aviation piston engines,marine and railroad diesel engines, automatic transmission fluids,transaxle lubricants, metalworking lubricants, hydraulic fluids, andother lubricating oil and grease compositions can also benefit from theincorporation of the present compositions.

Natural oils include animal oils and vegetable oils (e.g., castor oil,lard oil) as well as solvent-refined or acid-refined mineral lubricatingoils of the paraffinic, naphthenic, or mixed paraffinic-naphthenictypes. Oils of lubricating viscosity derived from coal or shale are alsouseful base oils. Synthetic lubricating oils include hydrocarbon oilsand halo-substituted hydrocarbon oils such as polymerized andinterpolymerized olefins (e.g., polybutylenes, polypropylenes,propylene-isobutylene copolymers, chlorinated polybutylenes, etc.);alkylbenzenes (e.g., dodecylbenzenes, tetradecylbenzene,dinonylbenzenes, di-(2-ethylhexyl)benzenes, etc.); polyphenyls (e.g.,biphenyls, terphenyls, etc.); and the like. Alkylene oxide polymers andinterpolymers and derivatives thereof where the terminal hydroxyl groupshave been modified by esterification, etherification, etc., constituteanother class of known synthetic lubricating oils. These are exemplifiedby the oils prepared through polymerization of ethylene oxide orpropylene oxide, the alkyl and aryl ethers of these polyoxyalkylenepolymers (e.g., methylpolyisopropylene glycol ether having an averagemolecular weight of 1,000, diphenyl ether of polyethylene glycol havinga molecular weight of 500-l,000, diethyl ether of polypropylene glycolhaving a molecular weight of 1,000-1 ,500, etc.) or monoandpolycarboxylic esters thereof, for example, the acetic acid esters,mixed C -C fatty acid esters, or the C Oxo acid diester of tetraethyleneglycol. Another suitable class of synthetic lubricating oils comprisesthe esters of dicarboxylic acids (e.g., phthalic acid, succinic acid,maleic acid, azelaic acid, suberic acid, sebacic acid, fumaric acid,adipic acid, linoleic acid dimer, etc.) with a variety of alcohols(e.g., butyl alcohol, hexyl alcohol, dodecyl alcohol, 2ethylhexylalcohol, pentaerythritol, etc.). Specific examples of these estersinclude dibutyl adipate, di(2-ethylhexyl) sebacate, di-n-hexyl fumarate,dioctyl sebacate, diisooctyl azelate, diisodecyl azelate, dioctylphthalate, didecyl phthalate, dieicosyl sebacate, the 2- ethylhexyldiester of linoleic acid dimer, the complex ester formed by reacting 1mole of sebacic acid with two moles of tetraethylene glycol and 2 molesof 2-ethylhexanoic acid, and the like. Silicon-based oils such as thepolyalkyl-, polyaryl-, polyalkoxy-, or polyaryloxy-siloxane oils andsilicate oils comprise another useful class of synthetic lubricants(e.g., tetraethyl silicate, tetraisopropyl silicate,tetra-(Z-ethyl-hexyl) silicate, tetra-(4-methyl-2-tetraethyl) silicate,tetra-(p-tert-butylphenyl) silicate,hexyl-(4-methyl-2-pentoxy)-disiloxane, poly(methyl)-siloxanes,poly(methylphenyl)-siloxanes, etc.). Other synthetic lubricating oilsinclude liquid esters of phosphorus-containing acids (e.g., tricresylphosphate, trioctyl phosphate, diethyl ester of decane phosphonic acid,etc.), polymeric tetrahydrofurans, and the like.

In general, about 005-200 parts (by weight) of the composition of thisinvention is dissolved in 100 parts of oil to produce a satisfactorylubricant. The invention also contemplates the use of other additives incombination with the products of this invention. Such additives include,for example, detergents and dispersants of the ash-containing or ashlesstype, viscosity index improvers, auxiliary corrosion and oxidationinhibiting agents, pour point depressing agents, auxiliary extremepressure agents, color stabilizers and anti-foam agents.

The ash-containing detergents are exemplified by oil-soluble neutral andbasic salts of alkali or alkaline earth metals with sulfonic acids,carboxylic acids, or organic phosphorus acids characterized by at leastone direct carbon-tophosphorus linkage such as those prepared by thetreatment of an olefin polymer (e.g., polyisobutene having a molecularweight of 1,000) with a phosphorizing agent such as phosphorustrichloride. phosphorus heptasulfide, phosphorus pentasulfide,phosphorus trichloride and sulfur, white phosphorus and a sulfur halide,or phosphorothioic chloride. The most commonly used salts of such acidsare those of sodium, potassium. lithium, calcium, magnesium, strontiumand barium.

The term basic salt is used to designate metals salts wherein the metalis present in stoichiometrically larger amounts than the organic acidradical. The commonly employed methods for preparing the basic saltsinvolve heating a mineral oil solution of an acid with a stiochiometricexcess of a metal neutralizing agent such as the metal oxide, hydroxide,carbonate, bicarbonate, or sulfide at a temperature above 50 C. andfiltering the resulting mass. The use of a promoter in theneutralization step to aid the incorporation of a large excess of metallikewise is known. Examples of compounds useful as the promoter includephenolic substances such as phenol, naphthol, alkylphenol, thiophenol,sulfurized alkylphenol, and condensation products of formaldehyde with aphenolic substance; alcohols such as methanol, 2-propanol, octylalcohol, cellosolve, carbitol, ethylene glycol, stearyl alcohol, andcyclohexyl alcohol; and amines such as aniline, phenylenediamine,phenothiazine, phenyl-B-naphthylamine and dodecylamine. A particularlyeffective method for preparing the basic salts comprises mixing an acidwith an excess of a basic alkaline earth metal neutralizing agent, aphenolic promoter compound, and a small amount of water and carbonatingthe mixture at an elevated temperature such as 60200bL C.

Ashless detergents and dispersants are illustrated by the interpolymersof an oil-solubilizing monomer, e.g., decyl methacrylate, vinyl decylether, or high molecular weight olefin, with a monomer containing polarsubstitutents, e.g., amino-alkyl acrylate orpoly-(oxyethylene)-substituted acrylate; the amine salts, amide, andimides of oil-soluble monocarboxylic or dicarboxylic acids such asstearic acid, oleic acid, tall oil acid, and high molecular weight alkylor alkenyl-substituted succinic acid. Especially useful as ashlessdetergents are the acylated polyamines and similar nitrogen compoundscontaining at least about 54 carbon atoms as described in U.S. Pat. No.3,272,746; reaction products of such compounds with other reagentsincluding boron compounds, phosphorus compounds, epoxides, aldehydes,organic acids and the like; and esters of hydrocarbon-substitutedsuccinic acids as described in U.S. Pat. No. 3,381,022.

Auxiliary extreme pressure agents and corrosion-inhibiting andoxidation-inhibiting agents are exemplified by chlorinated aliphatichydrocarbons such as chlorinated wax; organic sultides and polysulfidessuch as benzyl disulfide, bis- (chlorobenzyl) disulfide, dibutyltetrasulfide, sulfurized sperm oil, sulfurized methyl ester of oleicacid, sulfurized alkylphenol, sulfurized dipentene, and sulfurizedterpene; oil-soluble xanthates and trithiocarbamates; phosphosulfurizedhydrocarbons such as the reaction product of a phosphorus sulfide withturpentine or methyl oleate; phosphorus esters including principallydihydrocarbon and trihydrocarbon phosphites such as dibutyl phosphite,dihepthyl phosphite, dicyclohexyl phosphite, pentyl phenyl phosphite,dipentyl phenyl phosphite, tridecyl phosphite, distearyl phosphite,dimethyl naphthyl phosphite, oleyl 4-pentyl-phenyl phosphite,

polypropylene (molecular weight 500)-substituted phenyl phosphite,diisobutylrsubstituted phenyl phosphite; metal thiocarbamates, such aszinc dioctyldithiocarbamate, and barium heptylphenyl dithiocarbamate;Group 11 metal phosphorodithioates such as zincdicyclohexylphosphorodithioate, zinc dioctylphosphorodithioate, bariumdi(heptylphenyl)phosphorodithioate, cadmium dinonylphosphorothioate, andthe zinc salt of a phosphorodithioic acid produced by the reaction ofphosphorus pentasulfide with an equimolar mixture of isopropyl alcoholand n-hexyl alcohol.

While the compositions of this invention may be added directly in thedesired concentrations to lubricating oils prior to use, it is generallymore convenient to prepare concentrates containing one or more additivesincluding the compositions of this invention, dissolved in a smallamount of oil, and subsequently to add these concentrates to thelubricating oil in the desired amounts.

and is operated at 2,500 r.p.m. for 4 hours at 180 F. The temperature isthen reduced to 125 F. and the unit is stored for 7 days at thistemperature, after which time the assembly is drained and dismantled.Inspection for corrosion is made of the cover, the most corroded bearingand the most corroded gear in the unit, and these parts are rated on ascale of 0-10, 0 representing severe corrosion and 10 representing nocorrosion.

When tested by this method. lubricant A gave a cover rating of 9.8, abearing rating of 10 and a gear rating of 9.9. Lubricant B gave a coverrating of 9.94, a bearing rating of 10 and a gear rating of 10.

What is claimed is:

1. A method for preparing a composition of matter suitable for use as alubricant additive, which method comprises bringing into contact, underconditions such that a chemical reaction can take place, (A) a compoundof the formula R1 R The compositions of typical concentrates are givenin Table 1. in Table 11 are listed typical lubricating compositions ofthis invention. H

TABLE I Parts by weight Ingredient/Concentrate I II III IV V VI VII VIIIIX Product of Example 13.. Product of Example 14 Product of Example 18..Product of Example 20.. Zinc 0,0-di-(2-methyl-4-pentyl) dithioateTetrapropenylsnecinic acid IIydroxypropyl tetrapropenylsuceinate/tetrapropenylsuccinic acid mixture Tricresyl phosphate Alkylatedbisphenolsolution in inert i l l I I I I I I D h I organic solvent)lfi-di-t-butyl-pm'esol Snlfurizedisobutene 2-olcyl3.4.5.64etrahydropyrimidine.. Oleanlide-linolemuide mixture Siliconennti-lolnn ngent Mineral oil TABLE II Parts by weight Ingredient/Lubricant A B C D E F G The corrosion-inhibiting properties ofthe compositions of this invention are shown by a Copper Corrosion Testwhich is a modification of ASTM procedure D130. In this test, a polishedcopper strip is submerged in the lubricant being tested at 250 F. for 3hours, washed with isooctane and dried. 6 5 The copper strip is thenexamined to determine the amount of tarnish or corrosion, and iscompared with a set of ASTM standard strips on a scale of l, 2, 3 and 4representing slight tarnish, moderate tarnish, dark tarnish andcorrosion respectively. When tested by this method, Lubricants A and Beach gave ratings bordering between 1 and 2.

The Spicer Moisture Corrosion Test is used to determine the moisturecorrosion resistance characteristics of gear lubricants contaminated bywater in the normal environment of an automotive rear axle. in thistest, a sealed rear axle assembly is charged with 2V2 pints of gearlubricant and 1 ounce of water wherein each of R, R and R is hydrogen ora hydrocarbon radical; (B) carbon disulfide; and (C) a compositionprepared by forming an acidic intermediate by the reaction of ahydroxy-substituted triester of a phosphorothioic acid with an inorganicphosphorus acid, oxide or halide and neutralizing a substantial portionof said acidic intermediate with an amine.

2. A method according to claim 1 wherein component A is hydrazine orhydrazine hydrate.

3. A method according to claim 2 wherein the phosphorothioic acidtriester of component C has the formula wherein each R is a hydrocarbonradical or a hydroxy-substituted derivative thereof, at least one of theR radicals being hydroxy-substituted, and each X is sulfur or oxygen, atleast one of the X radicals being sulfur.

4. A method according to claim 3 wherein the phosphorothioic acidtriester has the formula wherein R is a monovalent and R is a divalenthydrocarbon radical.

5. A method according to claim 4 wherein the inorganic phosphoruscompound is a phosphorus oxide.

6. A method according to claim 5 wherein R is an alkyl radical and R isan alkylene radical.

7. A method according to claim 6 wherein R is lower alkyl and R is loweralkylene.

8. A method according to claim 7 wherein the amine of component C is analiphatic amine having about four to 30 carbon atoms.

9. A method according to claim 8 wherein the amine is a tertiary alkylprimary amine containing at least about eight carbon atoms.

10. A composition of matter prepared by the method of claim 2.

11. A composition of matter prepared by the method of claim 4.

12. A composition of matter prepared by the method of claim 7.

13. A composition of matter prepared by the method of claim 8.

14. A composition of matter prepared by the method of claim 9.

15. A lubricating composition comprising a major amount of a lubricatingoil and a minor amount, sufiicient to improve the lubricating propertiesthereof, of the composition of claim 10.

16. A lubricating composition comprising a major amount of a lubricatingoil and a minor amount, sufficient to improve the lubricating propertiesthereof, of the composition of claim 1 1.

17. A lubricating composition comprising a major amount of a lubricatingoil and a minor amount, sufiicient to improve the lubricating propertiesthereof, of the composition of claim 12 18. A lubricating compositioncomprising a major amount of a lubricating oil and a minor amount,sufficient to improve the lubricating properties thereof, of thecomposition of claim 13.

19. A lubricating composition comprising a major amount of a lubricatingoil and a minor amount, sufficient to improve the lubricating propertiesthereof, of the composition of claim 14.

2. A method according to claim 1 wherein component A is hydrazine orhydrazine hydrate.
 3. A method according to claim 2 wherein thephosphorothioic acid triester of component C has the formula whereineach R is a hydrocarbon radical or a hydroxy-substituted derivativethereof, at least one of the R radicals being hydroxy-substituted, andeach X is sulfur or oxygen, at least one of the X radicals being sulfur.4. A method according to claim 3 wherein the phosphorothioic acidtriester has the formula wherein R4 is a monovalent and R5 is a divalenthydrocarbon radical.
 5. A method according to claim 4 Wherein theinorganic phosphorus compound is a phosphorus oxide.
 6. A methodaccording to claim 5 wherein R4 is an alkyl radical and R5 is analkylene radical.
 7. A method according to claim 6 wherein R4 is loweralkyl and R5 is lower alkylene.
 8. A method according to claim 7 whereinthe amine of component C is an aliphatic amine having about four to 30carbon atoms.
 9. A method according to claim 8 wherein the amine is atertiary alkyl primary amine containing at least about eight carbonatoms.
 10. A composition of matter prepared by the method of claim 2.11. A composition of matter prepared by the method of claim
 4. 12. Acomposition of matter prepared by the method of claim
 7. 13. Acomposition of matter prepared by the method of claim
 8. 14. Acomposition of matter prepared by the method of claim
 9. 15. Alubricating composition comprising a major amount of a lubricating oiland a minor amount, sufficient to improve the lubricating propertiesthereof, of the composition of claim
 10. 16. A lubricating compositioncomprising a major amount of a lubricating oil and a minor amount,sufficient to improve the lubricating properties thereof, of thecomposition of claim
 11. 17. A lubricating composition comprising amajor amount of a lubricating oil and a minor amount, sufficient toimprove the lubricating properties thereof, of the composition of claim12.
 18. A lubricating composition comprising a major amount of alubricating oil and a minor amount, sufficient to improve thelubricating properties thereof, of the composition of claim
 13. 19. Alubricating composition comprising a major amount of a lubricating oiland a minor amount, sufficient to improve the lubricating propertiesthereof, of the composition of claim 14.